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163 个结果
  • 简介:NocathiacinI,aglycosylatedthiopeptideantibiotic,displaysexcellentantibacterialactivitiesagainstmultidrugresistantbacterialpathogens.Previously,anovelnocathiacinIformulationforintravenousadministrationhasbeensuccessfullydevelopedanditsaqueoussolubilityisgreatlyenhancedforclinicalapplication.ThepurposeofthepresentstudywastoincreasethefermentationtiterofnocathiacinIandreduceoreliminateanalogousimpuritiesbyscreeningthemediumingredientsusingresponsesurfacemethodology.Afterasysmaticoptimization,awater-solublemediumcontainingquality-controllablecomponentswasdevelopedandvalidated,resultinginanincreaseintheproductionofnocathiacinIfrom150to405.8mg·L-1at150-Lscale.Meanwhile,theanalogousimpuritiesexistedinreportedprocessesweregreatlyreducedoreliminated.Usingoptimizedmediumforfermentation,nocathiacinIwithpharmaceuticallyacceptablequalitywaseasilyobtainedwitharecoveryof67%.Inconclusion,theresultsfromthepresentstudyofferapracticalandefficientfermentationprocessfortheproductionofnocathiacinIasatherapeuticagent.

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  • 简介:Biot流动和喷射流动是在包含液体的多孔的媒介的二很重要的液体流动机制。基于二机制同时被对待的BISQ(Biot喷射)模型,在多孔的媒介的有弹性的波浪地模拟被限制到二尺寸、二部件(2D2C)或二尺寸、三部件(2D3C)。波浪模拟在上没有以前的报告三尺寸、三部件。仅仅通过三维的数字模拟,我们能有在双阶段的各向异性的媒介联合在固体和液体阶段之间的关系和空间分发特征的波浪地的全面理解。在这篇论文,基于BISQ方程,我们在三维的双阶段的各向异性的媒介的现在的有弹性的波浪繁殖由蹒跚格子的高顺序的有限差别的方法模仿了。我们分析产生波浪地并且证明结果是改进。

  • 标签: BISQ模型 三维空间数值模拟 交错栅格 各向异性
  • 简介:Extractionofthein-mediumpropertiesofstrangeparticlesfromheavy-ioncollisionsisverycomplicated,sincehenucleardensityvariesintheevolutionofnucleus-nucleuscollisions.Toavoidtheuncertaintiesofthebaryonensitiesduringthestageofstrangeparticleproduction,onecaninvestigateproton-nucleuscollisionswheretheucleardensityisdefinitearoundthesaturationdensity.DynamicsofstrangeparticlesproducedintheprotoninduceduclearthereactionsnearthethresholdenergieshasbeeninvestigatedwithintheLanzhouquantumoleculardynamics(LQMD)transportmodel.Thein-mediummodificationsonparticleproductionindensenuclearmatterareconsideredthroughthecorrectionstotheelementarycrosssectionsviatheeffectivemassandhemean-fieldpotentials[1].

  • 标签: STRANGE PARTICLES In-medium
  • 简介:BasedonthesolutionsoftheGreen'sfunctionforasaturatedporousmediumobtainedbytheauthors,andusingtransformationofaxisymmetriccoordinates,Sommerfeldintegralsandsuperpositionoftheinfluencefieldonafreesurface,theauthorshaveobtaineddisplacementsolutionsofasaturatedporousmediumsubjectedtoatorsionalforceinahalf-space.Therelationshipcurvesofthedisplacementsolutionsandvariousparameters(permeability,frequency,etc.)underactionofaunitoftorquearealsogiveninthispaper.TheresultsareconsistentwithpreviousReissner'ssolutions,whereatwo-phasemediumdecaystoasingle-phasemedium.Thesolutionisusefulinsolvingrelevantdynamicproblemsofatwophasesaturatedmediuminengineering.

  • 标签: 饱和多孔介质 半空间 Sommerfeld积分 扭转 两相饱和介质 自由表面
  • 简介:Amodelofdoublemediumaquiferisbrieflyintroducedinthispaper,apartialdifferentialequationaboutseepagemotionderivedbythetidalstressinthemodellayerisdeduced.ComparedthisequationwithBoultonequationusedintheunconfinedaquifer,anewlaggingsupplywatertermisobtained,whichestablishthephysicalbasisforinterpretingthephasedelayphenomenaofwellwaterlevelcausedbythesolidtide.Byanalyzingthepartialdif-ferentialequation,itisfoundthatthislaggingsupplytermisrelatedwiththefluctuationoftideoccurredinthedeepaquifer.

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  • 简介:Theinfluenceofdirectquenching(DQ)onmicrostructureandmechanicalpropertiesof0.19C-1.7Si-1.0Mn-0.05Nbsteelwasstudied.Themicrostructureandmechanicalpropertiesofreheatquenchedandtempered(RQ&T)steelplatewerecomparedwiththoseofdirectquenchedandtempered(DQ&T)steelplateswhichwerehotrolledatdifferentfinishrollingtem-peratures(1173Kand1123K),i.e.,recrystallization-controlled-rolleddirect-quenched(RCR&DQ)andcontrolled-rolleddirect-quenched(CR&DQ),respectively.Thestrengthsgenerallyincreasedinthefollowingorder:RQ&T

  • 标签: 直接淬火 机械性能 显微组织 含铌钢 电子背散射衍射 透射电子显微镜
  • 简介:ThemechanismoftheinterfacialreactionofAl2O3/mediumMnsteelcontainingNbwasstudiedbymeansoftheobservationontheinterfacialreactionphenomenonofAl2O3/mediumMnsteel,andtheanalysesontheinterracialphases.TheresultsshowthatwhenT≥1550℃,theinterfacialreac-tionofAl2O3/mediumMnsteelcontainingNbhappened.InthemediumMnsteelmatrix,NbexistsintheformofNbC.NbCarethenucleatingbaseofCOgasbubbles.

  • 标签: NB MEDIUM Mn steel Al2O3 INTERFACIAL
  • 简介:UsingGPSobservationsofhorizontalmovementfrom2001to2003andthecross-faultmobileshort-levellingdataof1988~2003,andwiththeaidoftheimprovednegativedislocationmodelandthetime-varyingcurveofstrainintensityratiooffaultdeformation,theregionaltectonicdeformationbackgroundandmedium-andshort-termprecursorsrelatedtothepreparationoftheMinle-ShandanearthquakesofMs6.1andMs5.8onOctober25,2003areinvestigated.Theresultsrevealthat,underthebackgroundofthewide-rangedeformationadjustment,short-termrelaxationandrecoverycausedbytheKuulunMountainsearthquakeofMsS.1,thehypocentersoftheearthquakesarelocatedonthenorthedgeoftheshearstressenhancementzonebetweenthecompressionallockedsegmentsofblockboundaryfault,aplacewhichmayrepresentanacceleratedstrainaccumulation.Anobviousanomalyofstrainintensityratioappearedinshort-levellingmeasurementscrossingoverthefaultattheShihuiyaokousite,theclosesttotheepicenters,3monthsbeforetheoccurrenceoftheearthquakes.Inaddition,thevariationinnumberofanomaliesfrom10-odddaystomonthsbeforetheearthquakesintheentiremonitoringareaandtheanomalyconcentrationandlocalenhancementrelativetonearsourceinthe3monthsbeforetheearthquakesareregardedtobeprecursorstothetwoevents.

  • 标签: 全球卫星定位观测 地质形变 地壳位移模型 断层 地震预报
  • 简介:AbstractPurpose:The COVID-19 pandemic has caused 1.4 million deaths globally and is associated with a 3-4 times increase in 30-day mortality after a fragility hip fracture with concurrent COVID-19 infection. Typically, death from COVID-19 infection occurs between 15 and 22 days after the onset of symptoms, but this period can extend up to 8 weeks. This study aimed to assess the impact of concurrent COVID-19 infection on 120-day mortality after a fragility hip fracture.Methods:A multi-centre prospective study across 10 hospitals treating 8% of the annual burden of hip fractures in England between 1st March and 30th April, 2020 was performed. Patients whose surgical treatment was payable through the National Health Service Best Practice Tariff mechanism for "fragility hip fractures" were included in the study. Patients’ 120-day mortality was assessed relative to their perioperative COVID-19 status. Statistical analysis was performed using SPSS version 27.Results:A total of 746 patients were included in this study, of which 87 (11.7%) were COVID-19 positive. Mortality rates at 30- and 120-day were significantly higher for COVID-19 positive patients relative to COVID-19 negative patients (p < 0.001). However, mortality rates between 31 and 120-day were not significantly different (p = 0.107), 16.1% and 9.4% respectively for COVID-19 positive and negative patients, odds ratio 1.855 (95% CI 0.865-3.978).Conclusion:Hip fracture patients with concurrent COVID-19 infection, provided that they are alive at day-31 after injury, have no significant difference in 120-day mortality. Despite the growing awareness and concern of "long-COVID" and its widespread prevalence, this does not appear to increase mediumterm mortality rates after a hip fracture.

  • 标签: Hip fractures Femoral fractures COVID-19 Coronavirus Mortality
  • 简介:WereportontheexperimentalrealizationofCerenkovsum-frequencygenerationacrossthematerialdispersioninaone-dimensional,periodicallypoledferroelectriccrystal.Threeschemesofsum-frequencygeneration,confinedonlyinthevicinityofdomainwallsandintheformofnonlinearCerenkovradiation,aredemonstratedinnormal,degenerated,andanomalous-dispersion-likeconfigurations.Weexploittheirphase-matchinggeometries,whichexhibitawholescenariooftheevolutionofCerenkovradiationvaryingwiththedispersionrelationshipamongtheinteractionwaves.Inaddition,twosetsofconicalsum-frequencygenerationwithdifferentradiusandcenteraredemonstrated,whichresultfromscatteringassistantphase-matchingprocesses.

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  • 简介:Thediscrete-ordinatesmethodisasimple,accurateandoflittlecomputationaltimesolutiontopredicttheradiactiveheattransferinthecombustionchambers,Inthispaper,three-dimensionradiativeproblemsforabsorbing-emitting-scatteringmediumaremodeledusingthismethodintherectangularenclosure.Andinaddition,newdiscrete-ordinatesaredevelopedtostudytheabsorbing-emitting-scatteringradiationprocessesforcomplexphasefunction.Thereasonableresultscanbeobtainedthoughthesenewordinates,yetthedeviatedresultsareonlyobtainedthroughconventionalSnordinates.

  • 标签: 三维辐射 吸收-发射-散射介质 分立竖标距
  • 简介:Basedontheporousmediatheoryandbytakingintoaccounttheeffectsoftheporefluidviscidity,energyexchangesduetotheadditionalthermalconductionandconvectionbetweensolidandfluidphases,amathematicalmodelforthedynamic-thermo-hydro-mechanicalcouplingofanon-localthermalequilibriumfluid-saturatedporousmedium,inwhichthetwoconstituentsareassumedtobeincompressibleandimmiscible,isestablishedundertheassumptionofsmalldeformationofthesolidphase,smallvelocityofthefluidphaseandsmalltemperaturechangesofthetwoconstituents.Themathematicalmodelofalocalthermalequilibriumfluid-saturatedporousmediumcanbeobtaineddirectlyfromtheaboveone.SeveralGurtin-typevariationalprinciples,especiallyHu-Washizutypevariationalprinciples,fortheinitialboundaryvalueproblemsofdynamicandquasi-staticresponsesarepresented.Itshouldbepointedoutthatthesevariationalprinciplescanbedegeneratedeasilyintothecaseofisothermalincompressiblefluid-saturatedelasticporousmedia,whichhavebeendiscussedpreviously.

  • 标签: 热局部热等效 热力学耦合 数学模型 变化原则 多孔介质